HONOLULU — Tourists in Oahu and other popular parts of Hawaii got back to their beach vacations and residents lined up to vote in primary elections today, a day after Tropical Storm Iselle swept through the islands without widespread disaster. But a large, rural swath of the Big Island has spent more than 24 hours without electricity and is struggling with downed trees blocking roads.

Iselle made landfall early Friday over the lower Puna region in the isolated southeastern part of the island, bringing down heavy rain, unleashing violent winds and toppling trees. The mostly agricultural area is as big as the island of Oahu and quickly growing because of affordable property, but it’s nowhere near as populated as the tourist destination home to Waikiki Beach and Pearl Harbor.

Umbrellas, surfboards and kayaks were back today at Waikiki Beach, but surf shop worker Sparky Barros said business was still a little slow compared with a normal sunny day. It was damp and cloudy at the popular tourist spot, and rain was off and on throughout Honolulu, but people went about jogging, swimming and lying on the beach even as attention shifted toward Hurricane Julio. The storm was expected to pass roughly 160 miles northeast of the islands at its closest point early Sunday and linger near the state into Monday.

Back on the Big Island, Gene Lamkin knows that life in the sparsely populated, jungle-like Puna region, where unpaved roads of volcanic rock are not maintained by the county, means being prepared for the worst.

“Those that didn’t prepare are going to be in dire straits,” he said, speaking from a cellphone he charged using a generator. “We invested in a generator years ago, but this is the first time we’ve had to use it at a full-time capacity. We always have our shelves stocked with food and water.”

Tall albizia trees fell over roads, wind upended his neighbor’s chicken coops and a neighbor’s water catchment system, which most residents in the region rely on, was damaged.

“It’s like camping right now,” he said of being without electricity since 8:30 p.m. Thursday. “We’re using water from our catchment system to bathe ourselves, shampoo our hair — trying to remain in a civilized manner.”

Hawaii County Civil Defense Director Darryl Oliveira worries there could be injured people rescuers can’t reach.

“We’re hopeful even with the damage, we don’t have casualties that are unaccounted for,” he said.

Puna, which is home to about 40,000 people, had the bulk of the 9,200 customers still without power, according to Hawaii Electric Light Co. Outages could last through the weekend or longer, the utility said. At the height of the storm, about 25,000 customers lost electricity.

At a fire station today, the county gave out water, tarps and ice, which is in short supply for those without power.

Self-proclaimed storm-chaser Jeff Piotrowski of Oklahoma said he’s seen some crushed houses and power lines down on highways.

“There are literally tens of thousands of trees that are down,” he said, adding that there are long lines for gasoline. “This is a massive undertaking to get all these lines back up.”

Still, many were relieved that Iselle didn’t pack a bigger punch throughout the island chain.

“This was no Sandy or Katrina or any other storm that you remember the name of,” said Sylvia Dahlby, 58, of the Big Island’s more populated Hilo area.

Outside the hard-hit Puna region, residents and visitors went about a seemingly normal weekend.

In Waikiki, tourists Ginny and George Gardner, who were celebrating their 42nd wedding anniversary, spent an extra day on Oahu after Iselle delayed their flight to Maui.

“We’re from Boston. This wasn’t a storm for us ... it was just a normal windy day,” Ginny Gardner said.

Primary election polls opened statewide at 7 a.m. HST today and voters were casting their ballots, said Rex Quidilla, spokesman for the Office of Elections. Two polling places in the Puna area of the Big Island were closed, with voters there to cast mail-in ballots after the election.

The Hawaii Department of Education said schools statewide will reopen Monday, except Waiakea High School on the Big Island, which needed more time to get ready after some 400 people used its facilities for a shelter from Thursday through Saturday.